The main difference between C3 and C4 plants is, C3 plants uses the C3 pathway and majority of plant son this Earth are C3 plants, while on the other hand, C4 plants uses the C4 pathway. C4 plants are less than C3 but they are efficient in carrying out the process of photosynthesis.
C3 plants are numerous and they use the C3 pathway. In C3 plants, the chloroplast is of one type, that is monomorphic and they do not have peripheral reticulum. The bundle sheath of C3 plants do not contain much chloroplast. Light reactions in the C3 plants occur in mesophyll cells where carbon fixation occurs with the help of ribulose bisphosphate carboxylase oxygenase. Incoming carbon dioxide reacts with G3P and goes through a series of reduction. These biochemical processes are almost similar in all plants.
C4 plants mostly dwell in warm water and moist climate. In the mesophyll cells of C4 plants, the oxygen is in more concentration rather than carbon dioxide. Oxygen concentration is high in these cells due to photolysis. C4 cycle is the alternate pathway of calvin cycle which takes place during the dark phase of photosynthesis. Oxaloacetic acid is the first compound of the C4 cycle and the leaves of these plants have special type of anatomy called krans anatomy.
- C3 plants uses C3 pathway and C4 plants uses C4 pathway.
- The leaves of C3 plants do not have krans anatomy but the leaves of C4 plants possess krans anatomy.
- Chloroplast is monomorphic in C3 plants and dimorphic in C4 plants.
- C3 plants are less efficient in carrying out photosynthesis than C4 plants.
- Chloroplast do not have peripheral reticulum in C3 plants but do have peripheral reticulum in C4 plants.
- Mesophyll cells perform complete photosynthesis in C3 plants but only initial fixation in C4 plants.
- C3 plants perform photosynthesis when stomata are open and C4 plants perform photosynthesis even when the stomata is closed.